Process of destroying cotton-boll weevils.



c infra-n STATES PATENT oFrioF- "WILMO'N NEWELL, OF COLLEGE STATION, TEXAS.

PROCESS OF DESTROYING- COTTON-BOLL WEEVILS.

Ifi'o Drawing. Original application filed November 20, 1909, Serial No. 529,131.

' tion filed March 4, 1912. Serial No. 681,626.

To all whom it may concern:

Be it known that I, YVILMONNEWELL, a

citizen of the United States of-America, now

residing at College Station, in the county of Brazos, in the State of Texas, have invented certain new and useful Improvements in Processes of Destroying Cotton-Boll \Veevils,

' whereof the following is a specification.

' weevil, or snout-beetle, as distinguished from a true biting or masticating insect, and does its feeding Within the folded,.appressed leaves constituting the terminal Whirl or bud at the growing tips of the cotton stems and limbs and within the involucre, or shuck,.. surrounding the fruiting bud or square. be effectively destroyed by the use of the usual arsenical poisons, such as Paris green, London purple,. etc., because applications of these poisons in moderate quantities do not result in the weevils securing enough arsenic inthe course of feeding upon the cotton plant to produce death.

The application of arsenical poisons heretofore commonly known, such as Paris green, London purple, white arsenic, arsenite of lime, lead arsenite, copper arsenite, and others, to 'the cotton plant in sufficient quantities to kill an appreciable number of boll weevils is followed by the death of or severe injury to the cotton plant itself becauseall of. these poisons contain watersoluble arsenic in quantities sufficient to exert a toxic effect upon the plant. henever arsenic in a soluble form, comes in contact with plant tissue, it is carried into, the tis sue itself by the water in which it is dissolved and the toxic or poisoning effect on the plant is the inevitable result.

Liquid sprays of ar'senical poisons, such for example as a liquid spray of the paste form of lead. arsenate, cannot be successfully used against the boil Weevil for thereason Specification of Letters Patent.

The boll weevil, therefore, cannot' Patented May 14., 1912.

Divided and this applicadrive the leaves composing them closer to gether and the presence of the moisture causes the leaves composing thesebuds to adhere to each. other tenaciously, thus excluding the spray no matter how much of it '1s applled or with what force it is applied.

Liquid sprays of arsenical poisons are impracticablefor the destruction of the boll weevil for the further reason that the cost of handling the enormous quantity of water required in spraying a cotton field is prohibitive of their. use.

This invention, which overcomes the obstacles referred to, consists in subjecting the buds of the cotton plant to the action of a bud-opening air-blast carrying lead arsenate in theform of a dry impalpable insoluble powder, and thereby depositing and distributing between and upon the leaves of said buds lead arsen'ate insufficient quantities to destroy boll weevils and in a form which prevents absorption of the poison by the plant. Such powder contains practically little or no water-soluble arsenic and thus avoids the destructive, or injurious eifect upon the-plants'incident to an appreciable presence of the last named ingredient, and the subjectiveness of arsenate in this form to application .by means of a bud-opening air-blast enables it to penetrate the terminal buds and the involucres of the squares in quantities sufiicient to destroy the boll weevils feedingtherei A strong current of air forees'apart the small leaves composing the bu'dsand the minute particles of powdered lead arsenate carried by the same air enter between the leaves and by impact are made to adhere thereto. The principal requisite of thisparticularphysical form of lead arsenate, is that it be reduced to an impalpable powder, or to a powder the individual particles of, which do not exceed about one one-thousandth of an inch in diameter. Any method of comminution which will result in the lead arsenate being re duced to such an iinpalpable powder will --In carrying out give toit the new and valuable characteristics herein described. Reduction of the lead arsenate to such an impalpable powder may be accomplished by mechanical means, or by a combination of both chemical and mechanical processes. Thus the following process accomplishes the desired end: Lead arsenate, made by the usual and well-known method of precipitating it from solutions of sodium arsenate and lead acetate, is dried as much as possible by slow heating. Thereafter the desiccation is completed by spreading the lead arsenate in thin layers within an air-tight chamber, in whiclris also contained a sufficient quantity of dehydrated calcium chlorid to absorb the remaining moisture. \Vhen entirely dried by thisprocess the arsenate of lead is reduced to the requisite degreeof comminution by grinding with pestleand mortar, or by grinding it between opposed steel, or other metal disks arranged after the manner of old fashioned millstones. Thereafter, to remove any particles not rendered sufficiently small by the grinding, the material is sifted through cloth of sulficiently fine mesh and is then ready for use. j

this method of destroying the cotton boll weevil a hand bellows may be employed to which is attached a receptacle for containing the powdered lead arsenate aforesaid and delivering it into the blast or current of air discharged by the bellows. The bellows air-blast containing insoluble impalpable lead arsenate is directed against the buds which are at theends of the limbs ofthe cotton plant and enters between said terminal buds or whirls of leaves carrying said arsenate with it. The current of air must have suflicient power to force apart the small leaves composing these buds and to deposit the minute particles of poison between them so that. they will be eaten by the boll weevil when feeding in these terminal buds, or whirls of leaves' In like manner the poison is forced into the inside of the involucre or shuck surroundin the square and there embedded in or caused to adhere to the eaidermis of the square itself, where it wil be eaten by the boll weevil-when it commences to puncture the square with its mouth-parts or beak.

In lieu of the application by a hand bellows as above described, the application of the powdered lead arsenate may be made with any suitable apparatus or machinery which will mechanically mix the poison with air, and using the air as a carrier, force the poison into the buds and squares of the cotton plant in the manner described.

Applications of the powdered lead arsenate at the rate of from two and one-half to ten pounds per acre are mosteffective in destroying the .boll weevils". The. amount applied depends upon the size of the cotton plants; and the applications may be repeated as many times as desired without injury to the plants. v

The powdered arsenate of lead, or lead arsenate, hereinbefore referred to, is defined as a finely powdered or pulverized dry dust, consisting of any one or more of the following compounds or mixtures: 1. Arsenate of lead known chemically by the formula Pb,(AsO,) and designated as lead ortho arsenate, or com-. mercially as lead arsenate. 2. Arsenate of lead known chemically by the formula PbHAsO designated as lead hydrogen arsenate. 3. Arsenate of lead known chemically by the formula Pb As O designated as lead pyro arsenate. t. Arsenate of lead known chemically by the formula Pb(AsO designated as lead meta arsenate. 5. Any lead salt corresponding chemically to the acids H AsO, (ortho ar senate acid), H,As,O,- (pyro arsenate acid);-

or HAsO (meta arsenate acid).- 6. Any

physical or chemical combination or arseni-' ous oxid (or oxids) with 'oxid (or oxids) of lead, or of arsenic oxid (or oxids) with oxid (or oxids) of lead, in-or without as-' soeiation with other ingredients,which shall be practically equivalent to, on chemical analysis, any one or more ofthe arsenates of lead hereinbefore named, or which shall produce the same physiological efiects upon,

plant and animal life as the arsenates of lead hereinbefore named. A

I The powdered or pulverized lead arsenate described should not contain more than onefifth of one per cent. of water-soluble arsenious oxid. Preferably it should not con tain exceeding one-tenth of one per cent. of water-soluble arsenious oxid.

The presence of a small amount of lead acetate, remaining from the original solutions of lead acetate and sodium arsenate,

used in precipitation of the lead arsenate,

does not appear to affect the usefulness of the completed, pulverized lead arsenate.

It is neither necessary nor'desirable that the 'lead arsenate should be precipitated from solution in such a manner as-to associate it with either active or inert particles of foreign substances; nor is it necessary nor desirable that said powdered orpulverized lead arsenate should be used with a diluent. It requiresno dilution and any substantial dilution thereof or mixture thereof with either active or inert foreign substances would reduce its effectiveness.

I claim asmy invention:

1. The process of treating the cotton plant for destroying the cotton boll weevil which consists in subjecting the buds of said plant to the action of a bud-opening air-blast carrying lead arsenate in the form of a dry practically insoluble impalpable powder which enters between the leaves and by impact adheres thereto..

2. The process of treating the cotton plant for destroying the cotton boll weevil which consists in subjecting the buds of said plant to the action of a bud-opening air-blast carrying lead arsenate in the form of a. dry

practically insoluble impalpabl powder WILMoN NEWE I Witnessesc I I W. G. TAIJAFERRO,

J. T. HANWAY.

Copiesof this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

- Washington, D, G. 

